A development that is said to open the way for all formal and casual shirt collars to be fused using a resin that will not reflow when subjected to elevated temperatures has been unveiled by Dritex International Ltd.

Top-fusing with thermoplastic resins has long been the favored process for manufacturing shirt collars, although the time taken by the fusing process requires thermoplastic resins that will melt and then solidify during the fusing cycle. To withstand continuous wash cycles, high density polyethylenes are generally used as the fusible resin, but excessive heat when ironing can cause the fusible resin to 'reflow' and damage the shirt collar. Post curing (wrinkle free processing) can also cause reflow.

For many years Dritex International has pioneered the development of Reactabond cross-linkable reactive resins. These resins will cross-link during the fusing cycle to produce an irreversible solid mass that will not reflow when subjected to further high temperature processing. The company's DT2030 grade was developed primarily to withstand post-curing processes. Its DT 2030, however, required two passes through the fusing press to achieve a full cure, and this extended fusing cycle was considered too costly in production time for shirts other than those requiring a post curing process.

The search has continued to produce a fusible resin that cures with one pass through the fusing press - and has now resulted in the development of grade DT 2425, a resin that can be used on formal and casual shirt collars yet will not reflow when subjected to elevated temperatures.

During the fusing process, the cross-linking reaction can create chemical bonds to both the interlining base fabric and the outer fabric, thus producing very high bond strengths and enhanced wash resistance. Very high levels of adhesion to filament nylon, polyester and polyester cotton have been reported. Changes in cloth finishing have often caused major problems in achieving satisfactory bond strength, but DT 2425 is said to bond extremely well to silicone, fluorocarbon and other water and stain repellant finishes.

The temperatures used to apply DT 2425 to interlining base fabrics are the same as those required for high-density polyethylene and the interlining is produced using conventional PowderPoint application equipment.